Field of the Invention
The present invention relates to an aircraft motor drive control apparatus that drives a three-phase motor mounted in an aircraft to drive a device installed in the aircraft and controls an operational status of this three-phase motor, and an aircraft actuator hydraulic system including an aircraft motor drive control apparatus.
Description of Related Art
Various electrically powered devices are installed in an aircraft, and such devices are driven by electric motors mounted in the aircraft. Examples of the aforementioned devices include an electrically powered hydraulic pump for supplying pressure oil to a hydraulically operated actuator that drives moving surfaces, as disclosed in JP2011-247334A. Note that the moving surfaces include primary flight control surfaces configured as control surfaces such as ailerons, rudders, elevators, and the like, and secondary flight control surfaces configured as flaps, spoilers, and the like. Also, other examples of the devices include an electric actuator for driving the aforementioned moving surfaces, or the struts (mechanism supporting the airframe of the aircraft on the ground) of a landing gear (undercarriage) or the like.
A three-phase motor is often used as an electric motor for driving the aforementioned devices. A motor drive control apparatus (aircraft motor drive control apparatus) that is also mounted in the aircraft drives the three-phase motor, and controls the operational status of the three-phase motor. Also, from the viewpoint of efficiency improvement, it is possible to use, as such a motor drive control apparatus, a motor drive control apparatus including a three-phase inverter circuit that has switching elements and drives a three-phase motor, and a controller that performs pulse width modulation control (PWM control) of this three-phase inverter circuit.
Also, JP2005-117869A discloses, as a motor drive control apparatus to be provided in a vehicle, a motor drive control apparatus that alternately fixes an on/off state of a switching element of one phase in a three-phase inverter circuit, and modulates on/off states of switching elements of the other two phases. In other words, JP 2005-117869A discloses a motor drive control apparatus that employs a so-called two-arm control method.